1. Field of the Invention
The present invention relates generally to a temperature variation apparatus, and more particularly, relates to a temperature variation apparatus for varying and controlling a temperature of a liquid.
2. Description of the Prior Art
Since the number of sequenced genomes is growing and more disease genes are found, molecular biology is a key knowledge in molecular diagnosis technology and medical diagnosis. Since the technique of polymerase chain reaction (PCR) was developed, molecular biology has been playing an important role in molecular medical diagnostics. Recently, the demand in molecular biological diagnosis and medical clinical diagnosis are growing, the precise and fast quantitative analysis technology is one of the key issues. In the scope of molecular medical diagnosis, real-time PCR is a main technology and has advantages of short testing time, high sensitivity, and various clinical specimens.
When the PCR is carried on, a thermo-cycle is repeated (e.g. denaturation, annealing, and extension), so the high sensitivity of the real-time PCR needs a heat conduction device with stable and precise thermal-control. Therefore, a temperature variation apparatus capable of quickly raising/decreasing temperature and precisely controlling temperature is crucial for the real-time PCR.
Traditionally, several plastic tubes filled with liquid are disposed on a heating region of a temperature variation apparatus, and then a heat source heats the heating region to heat the plastic tubes. In other words, the heat source heats the liquid in the plastic tubes through heating the region. Therefore, the actual temperature of the liquid is calculated based on the temperature of the heating region and some empirical calculations (results of experiments). Thus, it is hard to determine the temperature of the liquid precisely. Additionally, the plastic tubes are heated by one single heating region and thus it is difficult to individually control the temperature of each tube. Due to the fact that there is a certain area in the heating region the heat source heats only , the temperatures of different parts of the heating region are not consistent and have a gradient distribution, which results in the difficulty to precisely control the temperature of each tube.
To sum up, a traditional temperature variation apparatus does not satisfy the requirement of precise temperature control for real-time PCR. Thus the present invention provides a temperature variation apparatus capable of precisely varying and controlling temperature to solve the abovementioned problems.